1 /*
2 * Copyright (c) 2018, 2024, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "cds/archiveBuilder.hpp"
27 #include "cds/archiveHeapLoader.hpp"
28 #include "cds/archiveHeapWriter.hpp"
29 #include "cds/archiveUtils.hpp"
30 #include "cds/cdsConfig.hpp"
31 #include "cds/cdsEnumKlass.hpp"
32 #include "cds/cdsHeapVerifier.hpp"
33 #include "cds/classPreinitializer.hpp"
34 #include "cds/heapShared.hpp"
35 #include "cds/metaspaceShared.hpp"
36 #include "classfile/classLoaderData.hpp"
37 #include "classfile/javaClasses.inline.hpp"
38 #include "classfile/modules.hpp"
39 #include "classfile/stringTable.hpp"
40 #include "classfile/symbolTable.hpp"
41 #include "classfile/systemDictionary.hpp"
42 #include "classfile/systemDictionaryShared.hpp"
43 #include "classfile/vmClasses.hpp"
44 #include "classfile/vmSymbols.hpp"
45 #include "gc/shared/collectedHeap.hpp"
46 #include "gc/shared/gcLocker.hpp"
47 #include "gc/shared/gcVMOperations.hpp"
48 #include "logging/log.hpp"
49 #include "logging/logStream.hpp"
50 #include "memory/iterator.inline.hpp"
51 #include "memory/resourceArea.hpp"
52 #include "memory/universe.hpp"
53 #include "oops/compressedOops.inline.hpp"
54 #include "oops/fieldStreams.inline.hpp"
55 #include "oops/objArrayOop.inline.hpp"
56 #include "oops/oop.inline.hpp"
57 #include "oops/typeArrayOop.inline.hpp"
58 #include "prims/jvmtiExport.hpp"
59 #include "runtime/fieldDescriptor.inline.hpp"
60 #include "runtime/init.hpp"
61 #include "runtime/javaCalls.hpp"
62 #include "runtime/mutexLocker.hpp"
63 #include "runtime/safepointVerifiers.hpp"
64 #include "utilities/bitMap.inline.hpp"
65 #include "utilities/copy.hpp"
66 #if INCLUDE_G1GC
67 #include "gc/g1/g1CollectedHeap.hpp"
68 #endif
69
70 #if INCLUDE_CDS_JAVA_HEAP
71
72 struct ArchivableStaticFieldInfo {
73 const char* klass_name;
74 const char* field_name;
75 InstanceKlass* klass;
76 int offset;
77 BasicType type;
78
79 ArchivableStaticFieldInfo(const char* k, const char* f)
80 : klass_name(k), field_name(f), klass(nullptr), offset(0), type(T_ILLEGAL) {}
81
82 bool valid() {
83 return klass_name != nullptr;
84 }
85 };
86
87 class HeapShared::ArchivingObjectMark : public StackObj {
88 public:
89 ArchivingObjectMark(oop obj) {
90 _trace->push(obj);
91 }
92 ~ArchivingObjectMark() {
93 _trace->pop();
94 }
95 };
96
97 class HeapShared::ContextMark : public StackObj {
98 ResourceMark rm;
99 public:
100 ContextMark(const char* c) : rm{} {
101 _context->push(c);
102 }
103 ~ContextMark() {
104 _context->pop();
105 }
106 };
107
108 bool HeapShared::_disable_writing = false;
109 DumpedInternedStrings *HeapShared::_dumped_interned_strings = nullptr;
110
111 size_t HeapShared::_alloc_count[HeapShared::ALLOC_STAT_SLOTS];
112 size_t HeapShared::_alloc_size[HeapShared::ALLOC_STAT_SLOTS];
113 size_t HeapShared::_total_obj_count;
114 size_t HeapShared::_total_obj_size;
115
116 #ifndef PRODUCT
117 #define ARCHIVE_TEST_FIELD_NAME "archivedObjects"
118 static Array<char>* _archived_ArchiveHeapTestClass = nullptr;
119 static const char* _test_class_name = nullptr;
120 static const Klass* _test_class = nullptr;
121 static const ArchivedKlassSubGraphInfoRecord* _test_class_record = nullptr;
122 #endif
123
124
125 //
126 // If you add new entries to the following tables, you should know what you're doing!
127 //
128
129 static ArchivableStaticFieldInfo archive_subgraph_entry_fields[] = {
130 {"java/lang/Boolean", "archivedCache"},
131 {"java/lang/Integer$IntegerCache", "archivedCache"},
132 {"java/lang/Long$LongCache", "archivedCache"},
133 {"java/lang/Byte$ByteCache", "archivedCache"},
134 {"java/lang/Short$ShortCache", "archivedCache"},
135 {"java/lang/Character$CharacterCache", "archivedCache"},
136 {"java/util/jar/Attributes$Name", "KNOWN_NAMES"},
137 {"sun/util/locale/BaseLocale", "constantBaseLocales"},
138 {"jdk/internal/module/ArchivedModuleGraph", "archivedModuleGraph"},
139 {"java/util/ImmutableCollections", "archivedObjects"},
140 {"java/lang/ModuleLayer", "EMPTY_LAYER"},
141 {"java/lang/module/Configuration", "EMPTY_CONFIGURATION"},
142 {"jdk/internal/math/FDBigInteger", "archivedCaches"},
143 {"java/lang/invoke/DirectMethodHandle", "archivedObjects"}, // FIXME -- requires PreloadSharedClasses
144 {"java/lang/invoke/MethodType", "archivedObjects"}, // FIXME -- requires PreloadSharedClasses
145 {"java/lang/invoke/LambdaForm$NamedFunction", "archivedObjects"}, // FIXME -- requires PreloadSharedClasses
146 {"java/lang/reflect/Proxy$ProxyBuilder", "archivedData"}, // FIXME -- requires PreloadSharedClasses
147 #ifndef PRODUCT
148 {nullptr, nullptr}, // Extra slot for -XX:ArchiveHeapTestClass
149 #endif
150 {nullptr, nullptr},
151 };
152
153 // full module graph
154 static ArchivableStaticFieldInfo fmg_archive_subgraph_entry_fields[] = {
155 {"jdk/internal/loader/ArchivedClassLoaders", "archivedClassLoaders"},
156 {ARCHIVED_BOOT_LAYER_CLASS, ARCHIVED_BOOT_LAYER_FIELD},
157 {"java/lang/Module$ArchivedData", "archivedData"},
158 {nullptr, nullptr},
159 };
160
161 KlassSubGraphInfo* HeapShared::_default_subgraph_info;
162 ArchivedKlassSubGraphInfoRecord* HeapShared::_runtime_default_subgraph_info;
163 GrowableArrayCHeap<oop, mtClassShared>* HeapShared::_pending_roots = nullptr;
164 GrowableArrayCHeap<oop, mtClassShared>* HeapShared::_trace = nullptr;
165 GrowableArrayCHeap<const char*, mtClassShared>* HeapShared::_context = nullptr;
166 OopHandle HeapShared::_roots;
167 OopHandle HeapShared::_scratch_basic_type_mirrors[T_VOID+1];
168 MetaspaceObjToOopHandleTable* HeapShared::_scratch_java_mirror_table = nullptr;
169 MetaspaceObjToOopHandleTable* HeapShared::_scratch_references_table = nullptr;
170 int HeapShared::_permobj_segments = 0;
171
172 static bool is_subgraph_root_class_of(ArchivableStaticFieldInfo fields[], InstanceKlass* ik) {
173 for (int i = 0; fields[i].valid(); i++) {
174 if (fields[i].klass == ik) {
175 return true;
176 }
177 }
178 return false;
179 }
180
181 bool HeapShared::is_subgraph_root_class(InstanceKlass* ik) {
182 return is_subgraph_root_class_of(archive_subgraph_entry_fields, ik) ||
183 is_subgraph_root_class_of(fmg_archive_subgraph_entry_fields, ik);
184 }
185
186 unsigned HeapShared::oop_hash(oop const& p) {
187 // Do not call p->identity_hash() as that will update the
188 // object header.
189 return primitive_hash(cast_from_oop<intptr_t>(p));
190 }
191
192 static void reset_states(oop obj, TRAPS) {
193 Handle h_obj(THREAD, obj);
194 InstanceKlass* klass = InstanceKlass::cast(obj->klass());
195 TempNewSymbol method_name = SymbolTable::new_symbol("resetArchivedStates");
196 Symbol* method_sig = vmSymbols::void_method_signature();
197
198 while (klass != nullptr) {
199 Method* method = klass->find_method(method_name, method_sig);
200 if (method != nullptr) {
201 assert(method->is_private(), "must be");
202 if (log_is_enabled(Debug, cds)) {
203 ResourceMark rm(THREAD);
204 log_debug(cds)(" calling %s", method->name_and_sig_as_C_string());
205 }
206 JavaValue result(T_VOID);
207 JavaCalls::call_special(&result, h_obj, klass,
208 method_name, method_sig, CHECK);
209 }
210 klass = klass->java_super();
211 }
212 }
213
214 void HeapShared::reset_archived_object_states(TRAPS) {
215 assert(CDSConfig::is_dumping_heap(), "dump-time only");
216 log_debug(cds)("Resetting platform loader");
217 reset_states(SystemDictionary::java_platform_loader(), CHECK);
218 log_debug(cds)("Resetting system loader");
219 reset_states(SystemDictionary::java_system_loader(), CHECK);
220
221 // Clean up jdk.internal.loader.ClassLoaders::bootLoader(), which is not
222 // directly used for class loading, but rather is used by the core library
223 // to keep track of resources, etc, loaded by the null class loader.
224 //
225 // Note, this object is non-null, and is not the same as
226 // ClassLoaderData::the_null_class_loader_data()->class_loader(),
227 // which is null.
228 log_debug(cds)("Resetting boot loader");
229 JavaValue result(T_OBJECT);
230 JavaCalls::call_static(&result,
231 vmClasses::jdk_internal_loader_ClassLoaders_klass(),
232 vmSymbols::bootLoader_name(),
233 vmSymbols::void_BuiltinClassLoader_signature(),
234 CHECK);
235 Handle boot_loader(THREAD, result.get_oop());
236 reset_states(boot_loader(), CHECK);
237 }
238
239 HeapShared::ArchivedObjectCache* HeapShared::_archived_object_cache = nullptr;
240
241 bool HeapShared::has_been_archived(oop obj) {
242 assert(CDSConfig::is_dumping_heap(), "dump-time only");
243 return archived_object_cache()->get(obj) != nullptr;
244 }
245
246 int HeapShared::append_root(oop obj) {
247 assert(CDSConfig::is_dumping_heap(), "dump-time only");
248
249 // No GC should happen since we aren't scanning _pending_roots.
250 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
251
252 if (_pending_roots == nullptr) {
253 _pending_roots = new GrowableArrayCHeap<oop, mtClassShared>(500);
254 }
255
256 return _pending_roots->append(obj);
257 }
258
259 objArrayOop HeapShared::roots() {
260 if (CDSConfig::is_dumping_heap() && !CDSConfig::is_dumping_final_static_archive()) {
261 assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
262 if (!HeapShared::can_write()) {
263 return nullptr;
264 }
265 } else {
266 assert(CDSConfig::is_using_archive(), "must be");
267 }
268
269 objArrayOop roots = (objArrayOop)_roots.resolve();
270 assert(roots != nullptr, "should have been initialized");
271 return roots;
272 }
273
274 static unsigned int oop_handle_hash(const OopHandle& oh) {
275 oop o = oh.resolve();
276 if (o == nullptr) {
277 return 0;
278 } else {
279 return o->identity_hash();
280 }
281 }
282
283 static bool oop_handle_equals(const OopHandle& a, const OopHandle& b) {
284 return a.resolve() == b.resolve();
285 }
286
287 class OrigToScratchObjectTable: public ResourceHashtable<OopHandle, OopHandle,
288 36137, // prime number
289 AnyObj::C_HEAP,
290 mtClassShared,
291 oop_handle_hash,
292 oop_handle_equals> {};
293
294 static OrigToScratchObjectTable* _orig_to_scratch_object_table = nullptr;
295
296 void HeapShared::track_scratch_object(oop orig_obj, oop scratch_obj) {
297 MutexLocker ml(ArchivedObjectTables_lock, Mutex::_no_safepoint_check_flag);
298 if (_orig_to_scratch_object_table == nullptr) {
299 _orig_to_scratch_object_table = new (mtClass)OrigToScratchObjectTable();
300 }
301
302 OopHandle orig_h(Universe::vm_global(), orig_obj);
303 OopHandle scratch_h(Universe::vm_global(), scratch_obj);
304 _orig_to_scratch_object_table->put_when_absent(orig_h, scratch_h);
305 }
306
307 oop HeapShared::orig_to_scratch_object(oop orig_obj) {
308 MutexLocker ml(ArchivedObjectTables_lock, Mutex::_no_safepoint_check_flag);
309 if (_orig_to_scratch_object_table != nullptr) {
310 OopHandle orig(&orig_obj);
311 OopHandle* v = _orig_to_scratch_object_table->get(orig);
312 if (v != nullptr) {
313 return v->resolve();
314 }
315 }
316 return nullptr;
317 }
318
319 class ArchivedObjectPermanentIndexTable: public ResourceHashtable<OopHandle, int,
320 36137, // prime number
321 AnyObj::C_HEAP,
322 mtClassShared,
323 oop_handle_hash,
324 oop_handle_equals> {};
325
326 static ArchivedObjectPermanentIndexTable* _permanent_index_table = nullptr;
327
328 void HeapShared::add_to_permanent_index_table(oop obj, int index) {
329 assert_locked_or_safepoint(ArchivedObjectTables_lock);
330
331 if (_permanent_index_table == nullptr) {
332 _permanent_index_table = new (mtClass)ArchivedObjectPermanentIndexTable();
333 }
334 OopHandle oh(Universe::vm_global(), obj);
335 _permanent_index_table->put(oh, index);
336 }
337
338 int HeapShared::get_archived_object_permanent_index(oop obj) {
339 if (!UsePermanentHeapObjects) {
340 return -1;
341 }
342 if (!CDSConfig::is_dumping_heap() && _permobj_segments <= 0) {
343 return -1;
344 }
345
346 MutexLocker ml(ArchivedObjectTables_lock, Mutex::_no_safepoint_check_flag);
347
348 if (!CDSConfig::is_dumping_heap() && _permanent_index_table == nullptr) {
349 int first_permobj_segment = roots()->length() - _permobj_segments;
350 for (int i = 0; i < _permobj_segments; i++) {
351 objArrayOop a = (objArrayOop)roots()->obj_at(i + first_permobj_segment);
352 for (int j = 0; j < a->length(); j++) {
353 int index = (i << ArchiveHeapWriter::PERMOBJ_SEGMENT_MAX_SHIFT) + j;
354 add_to_permanent_index_table(a->obj_at(j), index);
355 }
356 }
357 }
358
359 if (_permanent_index_table != nullptr) {
360 if (_orig_to_scratch_object_table != nullptr) {
361 OopHandle orig(&obj);
362 OopHandle* v = _orig_to_scratch_object_table->get(orig);
363 if (v != nullptr) {
364 obj = v->resolve();
365 }
366 }
367 OopHandle tmp(&obj);
368 int* v = _permanent_index_table->get(tmp);
369 if (v != nullptr) {
370 int n = *v;
371 return n;
372 }
373 }
374
375 return -1;
376 }
377
378 oop HeapShared::get_archived_object(int permanent_index) {
379 if (ArchiveHeapLoader::is_in_use()) {
380 assert(_permobj_segments > 0, "must be");
381
382 int first_permobj_segment = roots()->length() - _permobj_segments;
383 int upper = permanent_index >> ArchiveHeapWriter::PERMOBJ_SEGMENT_MAX_SHIFT;
384 int lower = permanent_index & ArchiveHeapWriter::PERMOBJ_SEGMENT_MAX_MASK;
385 objArrayOop a = (objArrayOop)roots()->obj_at(upper + first_permobj_segment);
386 return a->obj_at(lower);
387 } else {
388 assert(CDSConfig::is_dumping_heap(), "must be");
389 return ArchiveHeapWriter::get_perm_object_by_index(permanent_index);
390 }
391 }
392
393 // Returns an objArray that contains all the roots of the archived objects
394 oop HeapShared::get_root(int index, bool clear) {
395 assert(index >= 0, "sanity");
396 assert(!CDSConfig::is_dumping_heap() && CDSConfig::is_using_archive(), "runtime only");
397 assert(!_roots.is_empty(), "must have loaded shared heap");
398 oop result = roots()->obj_at(index);
399 if (clear) {
400 clear_root(index);
401 }
402 return result;
403 }
404
405 void HeapShared::clear_root(int index) {
406 assert(index >= 0, "sanity");
407 assert(CDSConfig::is_using_archive(), "must be");
408 if (ArchiveHeapLoader::is_in_use()) {
409 if (log_is_enabled(Debug, cds, heap)) {
410 oop old = roots()->obj_at(index);
411 log_debug(cds, heap)("Clearing root %d: was " PTR_FORMAT, index, p2i(old));
412 }
413 roots()->obj_at_put(index, nullptr);
414 }
415 }
416
417 bool HeapShared::archive_object(oop obj) {
418 assert(CDSConfig::is_dumping_heap(), "dump-time only");
419
420 assert(!obj->is_stackChunk(), "do not archive stack chunks");
421 if (has_been_archived(obj)) {
422 return true;
423 }
424
425 if (ArchiveHeapWriter::is_too_large_to_archive(obj->size())) {
426 log_debug(cds, heap)("Cannot archive, object (" PTR_FORMAT ") is too large: " SIZE_FORMAT,
427 p2i(obj), obj->size());
428 return false;
429 } else {
430 count_allocation(obj->size());
431 ArchiveHeapWriter::add_source_obj(obj);
432 CachedOopInfo info = make_cached_oop_info(obj);
433 archived_object_cache()->put_when_absent(obj, info);
434 archived_object_cache()->maybe_grow();
435 mark_native_pointers(obj);
436
437 if (log_is_enabled(Debug, cds, heap)) {
438 ResourceMark rm;
439 log_debug(cds, heap)("Archived heap object " PTR_FORMAT " : %s",
440 p2i(obj), obj->klass()->external_name());
441 }
442
443 if (java_lang_Module::is_instance(obj) && Modules::check_archived_module_oop(obj)) {
444 Modules::update_oops_in_archived_module(obj, append_root(obj));
445 }
446
447 return true;
448 }
449 }
450
451 class MetaspaceObjToOopHandleTable: public ResourceHashtable<MetaspaceObj*, OopHandle,
452 36137, // prime number
453 AnyObj::C_HEAP,
454 mtClassShared> {
455 public:
456 oop get_oop(MetaspaceObj* ptr) {
457 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag);
458 OopHandle* handle = get(ptr);
459 if (handle != nullptr) {
460 return handle->resolve();
461 } else {
462 return nullptr;
463 }
464 }
465 void set_oop(MetaspaceObj* ptr, oop o) {
466 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag);
467 OopHandle handle(Universe::vm_global(), o);
468 bool is_new = put(ptr, handle);
469 assert(is_new, "cannot set twice");
470 }
471 void remove_oop(MetaspaceObj* ptr) {
472 MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag);
473 OopHandle* handle = get(ptr);
474 if (handle != nullptr) {
475 handle->release(Universe::vm_global());
476 remove(ptr);
477 }
478 }
479 };
480
481 void HeapShared::add_scratch_resolved_references(ConstantPool* src, objArrayOop dest) {
482 if (_scratch_references_table == nullptr) {
483 _scratch_references_table = new (mtClass)MetaspaceObjToOopHandleTable();
484 }
485 _scratch_references_table->set_oop(src, dest);
486 }
487
488 objArrayOop HeapShared::scratch_resolved_references(ConstantPool* src) {
489 return (objArrayOop)_scratch_references_table->get_oop(src);
490 }
491
492 void HeapShared::init_scratch_objects(TRAPS) {
493 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
494 BasicType bt = (BasicType)i;
495 if (!is_reference_type(bt)) {
496 oop m = java_lang_Class::create_basic_type_mirror(type2name(bt), bt, CHECK);
497 _scratch_basic_type_mirrors[i] = OopHandle(Universe::vm_global(), m);
498 track_scratch_object(Universe::java_mirror(bt), m);
499 }
500 }
501 _scratch_java_mirror_table = new (mtClass)MetaspaceObjToOopHandleTable();
502 if (_scratch_references_table == nullptr) {
503 _scratch_references_table = new (mtClass)MetaspaceObjToOopHandleTable();
504 }
505 }
506
507 // Given java_mirror that represents a (primitive or reference) type T,
508 // return the "scratch" version that represents the same type T.
509 // Note that if java_mirror will be returned if it's already a
510 // scratch mirror.
511 //
512 // See java_lang_Class::create_scratch_mirror() for more info.
513 oop HeapShared::scratch_java_mirror(oop java_mirror) {
514 assert(java_lang_Class::is_instance(java_mirror), "must be");
515
516 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
517 BasicType bt = (BasicType)i;
518 if (!is_reference_type(bt)) {
519 if (_scratch_basic_type_mirrors[i].resolve() == java_mirror) {
520 return java_mirror;
521 }
522 }
523 }
524
525 if (java_lang_Class::is_primitive(java_mirror)) {
526 return scratch_java_mirror(java_lang_Class::as_BasicType(java_mirror));
527 } else {
528 return scratch_java_mirror(java_lang_Class::as_Klass(java_mirror));
529 }
530 }
531
532 oop HeapShared::scratch_java_mirror(BasicType t) {
533 assert((uint)t < T_VOID+1, "range check");
534 assert(!is_reference_type(t), "sanity");
535 return _scratch_basic_type_mirrors[t].resolve();
536 }
537
538 oop HeapShared::scratch_java_mirror(Klass* k) {
539 return _scratch_java_mirror_table->get_oop(k);
540 }
541
542 void HeapShared::set_scratch_java_mirror(Klass* k, oop mirror) {
543 track_scratch_object(k->java_mirror(), mirror);
544 _scratch_java_mirror_table->set_oop(k, mirror);
545 }
546
547 void HeapShared::remove_scratch_objects(Klass* k) {
548 _scratch_java_mirror_table->remove_oop(k);
549 if (k->is_instance_klass()) {
550 _scratch_references_table->remove(InstanceKlass::cast(k)->constants());
551 }
552 }
553
554 bool HeapShared::is_lambda_form_klass(InstanceKlass* ik) {
555 return ik->is_hidden() &&
556 (ik->name()->starts_with("java/lang/invoke/LambdaForm$MH+") ||
557 ik->name()->starts_with("java/lang/invoke/LambdaForm$DMH+") ||
558 ik->name()->starts_with("java/lang/invoke/LambdaForm$BMH+"));
559
560 }
561
562 bool HeapShared::is_lambda_proxy_klass(InstanceKlass* ik) {
563 return ik->is_hidden() && (ik->name()->index_of_at(0, "$$Lambda+", 9) > 0);
564 }
565
566 bool HeapShared::is_archivable_hidden_klass(InstanceKlass* ik) {
567 return CDSConfig::is_dumping_invokedynamic() && (is_lambda_form_klass(ik) || is_lambda_proxy_klass(ik));
568 }
569
570 void HeapShared::copy_preinitialized_mirror(Klass* orig_k, oop orig_mirror, oop m) {
571 if (!orig_k->is_instance_klass()) {
572 return;
573 }
574 InstanceKlass* ik = InstanceKlass::cast(orig_k);
575
576 if (HeapShared::is_archivable_hidden_klass(ik)) {
577 // We can't rerun the <clinit> method of hidden classes as we don't save
578 // the classData, so we must archive its mirror in initialized state.
579 assert(ik->is_initialized(), "must be");
580 }
581
582 if (!ik->is_initialized() || !ClassPreinitializer::can_archive_preinitialized_mirror(ik)) {
583 return;
584 }
585
586 int nfields = 0;
587 for (JavaFieldStream fs(ik); !fs.done(); fs.next()) {
588 if (fs.access_flags().is_static()) {
589 fieldDescriptor& fd = fs.field_descriptor();
590 int offset = fd.offset();
591 switch (fd.field_type()) {
592 case T_OBJECT:
593 case T_ARRAY:
594 m->obj_field_put(offset, orig_mirror->obj_field(offset));
595 break;
596 case T_BOOLEAN:
597 m->bool_field_put(offset, orig_mirror->bool_field(offset));
598 break;
599 case T_BYTE:
600 m->byte_field_put(offset, orig_mirror->byte_field(offset));
601 break;
602 case T_SHORT:
603 m->short_field_put(offset, orig_mirror->short_field(offset));
604 break;
605 case T_CHAR:
606 m->char_field_put(offset, orig_mirror->char_field(offset));
607 break;
608 case T_INT:
609 m->int_field_put(offset, orig_mirror->int_field(offset));
610 break;
611 case T_LONG:
612 m->long_field_put(offset, orig_mirror->long_field(offset));
613 break;
614 case T_FLOAT:
615 m->float_field_put(offset, orig_mirror->float_field(offset));
616 break;
617 case T_DOUBLE:
618 m->double_field_put(offset, orig_mirror->double_field(offset));
619 break;
620 default:
621 ShouldNotReachHere();
622 }
623 nfields ++;
624 }
625 }
626 if (log_is_enabled(Info, cds, init)) {
627 ResourceMark rm;
628 log_debug(cds, init)("copied %3d field(s) in preinitialized mirror %s%s", nfields, ik->external_name(),
629 ik->is_hidden() ? " (hidden)" : "");
630 }
631
632 InstanceKlass* buffered_ik = ArchiveBuilder::current()->get_buffered_addr(ik);
633 buffered_ik->set_has_preinitialized_mirror();
634 }
635
636 static void copy_java_mirror_hashcode(oop orig_mirror, oop scratch_m) {
637 int src_hash = orig_mirror->identity_hash();
638 scratch_m->set_mark(markWord::prototype().copy_set_hash(src_hash));
639 assert(scratch_m->mark().is_unlocked(), "sanity");
640
641 DEBUG_ONLY(int archived_hash = scratch_m->identity_hash());
642 assert(src_hash == archived_hash, "Java mirror wrong hash: original %x, scratch %x", src_hash, archived_hash);
643 }
644
645 void HeapShared::archive_java_mirrors() {
646 ClassPreinitializer::reset_preinit_check();
647
648 for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
649 BasicType bt = (BasicType)i;
650 if (!is_reference_type(bt)) {
651 oop orig_mirror = Universe::java_mirror(bt);
652 oop m = _scratch_basic_type_mirrors[i].resolve();
653 assert(m != nullptr, "sanity");
654 copy_java_mirror_hashcode(orig_mirror, m);
655 bool success = archive_reachable_objects_from(1, _default_subgraph_info, orig_mirror);
656 assert(success, "sanity");
657
658 log_trace(cds, heap, mirror)(
659 "Archived %s mirror object from " PTR_FORMAT,
660 type2name(bt), p2i(m));
661
662 Universe::set_archived_basic_type_mirror_index(bt, append_root(m));
663 }
664 }
665
666 GrowableArray<Klass*>* klasses = ArchiveBuilder::current()->klasses();
667 assert(klasses != nullptr, "sanity");
668 for (int i = 0; i < klasses->length(); i++) {
669 Klass* orig_k = klasses->at(i);
670 oop orig_mirror = orig_k->java_mirror();
671 oop m = scratch_java_mirror(orig_k);
672 if (m != nullptr) {
673 copy_java_mirror_hashcode(orig_mirror, m);
674 copy_preinitialized_mirror(orig_k, orig_mirror, m);
675 if (CDSConfig::is_dumping_reflection_data() && java_lang_Class::has_reflection_data(orig_mirror)) {
676 oop reflection_data = java_lang_Class::reflection_data(orig_mirror);
677 bool success = archive_reachable_objects_from(1, _default_subgraph_info, reflection_data);
678 guarantee(success, "");
679 java_lang_Class::set_reflection_data(m, reflection_data);
680 }
681 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(orig_k);
682 bool success = archive_reachable_objects_from(1, _default_subgraph_info, orig_mirror);
683 guarantee(success, "scratch mirrors must point to only archivable objects");
684 buffered_k->set_archived_java_mirror(append_root(m));
685 ResourceMark rm;
686 log_trace(cds, heap, mirror)(
687 "Archived %s mirror object from " PTR_FORMAT,
688 buffered_k->external_name(), p2i(m));
689
690 // archive the resolved_referenes array
691 if (buffered_k->is_instance_klass()) {
692 InstanceKlass* ik = InstanceKlass::cast(buffered_k);
693 oop rr = ik->constants()->prepare_resolved_references_for_archiving();
694 if (rr != nullptr && !ArchiveHeapWriter::is_too_large_to_archive(rr)) {
695 bool success = HeapShared::archive_reachable_objects_from(1, _default_subgraph_info, rr);
696 assert(success, "must be");
697 int root_index = append_root(rr);
698 ik->constants()->cache()->set_archived_references(root_index);
699 }
700 }
701 }
702 }
703 }
704
705 void HeapShared::archive_strings() {
706 oop shared_strings_array = StringTable::init_shared_table(_dumped_interned_strings);
707 bool success = archive_reachable_objects_from(1, _default_subgraph_info, shared_strings_array);
708 // We must succeed because:
709 // - _dumped_interned_strings do not contain any large strings.
710 // - StringTable::init_shared_table() doesn't create any large arrays.
711 assert(success, "shared strings array must not point to arrays or strings that are too large to archive");
712 StringTable::set_shared_strings_array_index(append_root(shared_strings_array));
713 }
714
715 int HeapShared::archive_exception_instance(oop exception) {
716 bool success = archive_reachable_objects_from(1, _default_subgraph_info, exception);
717 assert(success, "sanity");
718 return append_root(exception);
719 }
720
721 void HeapShared::mark_native_pointers(oop orig_obj) {
722 if (java_lang_Class::is_instance(orig_obj)) {
723 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_Class::klass_offset());
724 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_Class::array_klass_offset());
725 } else if (java_lang_invoke_ResolvedMethodName::is_instance(orig_obj)) {
726 ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_invoke_ResolvedMethodName::vmtarget_offset());
727 }
728 }
729
730 void HeapShared::get_pointer_info(oop src_obj, bool& has_oop_pointers, bool& has_native_pointers) {
731 CachedOopInfo* info = archived_object_cache()->get(src_obj);
732 assert(info != nullptr, "must be");
733 has_oop_pointers = info->has_oop_pointers();
734 has_native_pointers = info->has_native_pointers();
735 }
736
737 void HeapShared::set_has_native_pointers(oop src_obj) {
738 CachedOopInfo* info = archived_object_cache()->get(src_obj);
739 assert(info != nullptr, "must be");
740 info->set_has_native_pointers();
741 }
742
743 void HeapShared::start_finding_archivable_hidden_classes() {
744 NoSafepointVerifier nsv;
745
746 init_seen_objects_table();
747
748 find_archivable_hidden_classes_helper(archive_subgraph_entry_fields);
749 if (CDSConfig::is_dumping_full_module_graph()) {
750 find_archivable_hidden_classes_helper(fmg_archive_subgraph_entry_fields);
751 }
752 }
753
754 void HeapShared::end_finding_archivable_hidden_classes() {
755 NoSafepointVerifier nsv;
756
757 delete_seen_objects_table();
758 }
759
760 void HeapShared::find_archivable_hidden_classes_helper(ArchivableStaticFieldInfo fields[]) {
761 if (!CDSConfig::is_dumping_heap()) {
762 return;
763 }
764 int i;
765 for (int i = 0; fields[i].valid(); ) {
766 ArchivableStaticFieldInfo* info = &fields[i];
767 const char* klass_name = info->klass_name;
768 for (; fields[i].valid(); i++) {
769 ArchivableStaticFieldInfo* f = &fields[i];
770 if (f->klass_name != klass_name) {
771 break;
772 }
773
774 InstanceKlass* k = f->klass;
775 oop m = k->java_mirror();
776 oop o = m->obj_field(f->offset);
777 if (o != nullptr) {
778 find_archivable_hidden_classes_in_object(o);
779 }
780 }
781 }
782 }
783
784 class HeapShared::FindHiddenClassesOopClosure: public BasicOopIterateClosure {
785 GrowableArray<oop> _stack;
786 template <class T> void do_oop_work(T *p) {
787 // Recurse on a GrowableArray to avoid overflowing the C stack.
788 oop o = RawAccess<>::oop_load(p);
789 if (o != nullptr) {
790 _stack.append(o);
791 }
792 }
793
794 public:
795
796 void do_oop(narrowOop *p) { FindHiddenClassesOopClosure::do_oop_work(p); }
797 void do_oop( oop *p) { FindHiddenClassesOopClosure::do_oop_work(p); }
798
799 FindHiddenClassesOopClosure(oop o) {
800 _stack.append(o);
801 }
802 oop pop() {
803 if (_stack.length() == 0) {
804 return nullptr;
805 } else {
806 return _stack.pop();
807 }
808 }
809 };
810
811 void HeapShared::find_archivable_hidden_classes_in_object(oop root) {
812 ResourceMark rm;
813 FindHiddenClassesOopClosure c(root);
814 oop o;
815 while ((o = c.pop()) != nullptr) {
816 if (!has_been_seen_during_subgraph_recording(o)) {
817 set_has_been_seen_during_subgraph_recording(o);
818
819 if (java_lang_Class::is_instance(o)) {
820 Klass* k = java_lang_Class::as_Klass(o);
821 if (k != nullptr && k->is_instance_klass()) {
822 SystemDictionaryShared::mark_required_class(InstanceKlass::cast(k));
823 }
824 } else if (java_lang_invoke_ResolvedMethodName::is_instance(o)) {
825 Method* m = java_lang_invoke_ResolvedMethodName::vmtarget(o);
826 if (m != nullptr && m->method_holder() != nullptr) {
827 SystemDictionaryShared::mark_required_class(m->method_holder());
828 }
829 }
830
831 o->oop_iterate(&c);
832 }
833 }
834 }
835
836 void HeapShared::archive_objects(ArchiveHeapInfo *heap_info) {
837 {
838 NoSafepointVerifier nsv;
839
840 _default_subgraph_info = init_subgraph_info(vmClasses::Object_klass(), false);
841 _trace = new GrowableArrayCHeap<oop, mtClassShared>(250);
842 _context = new GrowableArrayCHeap<const char*, mtClassShared>(250);
843
844 // Cache for recording where the archived objects are copied to
845 create_archived_object_cache();
846
847 if (UseCompressedOops || UseG1GC) {
848 log_info(cds)("Heap range = [" PTR_FORMAT " - " PTR_FORMAT "]",
849 UseCompressedOops ? p2i(CompressedOops::begin()) :
850 p2i((address)G1CollectedHeap::heap()->reserved().start()),
851 UseCompressedOops ? p2i(CompressedOops::end()) :
852 p2i((address)G1CollectedHeap::heap()->reserved().end()));
853 }
854 copy_objects();
855
856 if (!SkipArchiveHeapVerification) {
857 CDSHeapVerifier::verify();
858 }
859 check_default_subgraph_classes();
860 }
861
862 ArchiveHeapWriter::write(_pending_roots, heap_info);
863 }
864
865 void HeapShared::copy_interned_strings() {
866 init_seen_objects_table();
867
868 auto copier = [&] (oop s, bool value_ignored) {
869 assert(s != nullptr, "sanity");
870 assert(!ArchiveHeapWriter::is_string_too_large_to_archive(s), "large strings must have been filtered");
871 bool success = archive_reachable_objects_from(1, _default_subgraph_info, s);
872 assert(success, "must be");
873 // Prevent string deduplication from changing the value field to
874 // something not in the archive.
875 java_lang_String::set_deduplication_forbidden(s);
876 };
877 _dumped_interned_strings->iterate_all(copier);
878
879 delete_seen_objects_table();
880 }
881
882 void HeapShared::copy_special_objects() {
883 // Archive special objects that do not belong to any subgraphs
884 init_seen_objects_table();
885 archive_java_mirrors();
886 archive_strings();
887 Universe::archive_exception_instances();
888 delete_seen_objects_table();
889 }
890
891 void HeapShared::copy_objects() {
892 assert(HeapShared::can_write(), "must be");
893
894 copy_interned_strings();
895 copy_special_objects();
896
897 archive_object_subgraphs(archive_subgraph_entry_fields,
898 false /* is_full_module_graph */);
899
900 if (CDSConfig::is_dumping_full_module_graph()) {
901 archive_object_subgraphs(fmg_archive_subgraph_entry_fields,
902 true /* is_full_module_graph */);
903 Modules::verify_archived_modules();
904 }
905 }
906
907 //
908 // Subgraph archiving support
909 //
910 HeapShared::DumpTimeKlassSubGraphInfoTable* HeapShared::_dump_time_subgraph_info_table = nullptr;
911 HeapShared::RunTimeKlassSubGraphInfoTable HeapShared::_run_time_subgraph_info_table;
912
913 // Get the subgraph_info for Klass k. A new subgraph_info is created if
914 // there is no existing one for k. The subgraph_info records the "buffered"
915 // address of the class.
916 KlassSubGraphInfo* HeapShared::init_subgraph_info(Klass* k, bool is_full_module_graph) {
917 assert(CDSConfig::is_dumping_heap(), "dump time only");
918 bool created;
919 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(k);
920 KlassSubGraphInfo* info =
921 _dump_time_subgraph_info_table->put_if_absent(k, KlassSubGraphInfo(buffered_k, is_full_module_graph),
922 &created);
923 assert(created, "must not initialize twice");
924 return info;
925 }
926
927 KlassSubGraphInfo* HeapShared::get_subgraph_info(Klass* k) {
928 assert(CDSConfig::is_dumping_heap(), "dump time only");
929 KlassSubGraphInfo* info = _dump_time_subgraph_info_table->get(k);
930 assert(info != nullptr, "must have been initialized");
931 return info;
932 }
933
934 // Add an entry field to the current KlassSubGraphInfo.
935 void KlassSubGraphInfo::add_subgraph_entry_field(int static_field_offset, oop v) {
936 assert(CDSConfig::is_dumping_heap(), "dump time only");
937 if (_subgraph_entry_fields == nullptr) {
938 _subgraph_entry_fields =
939 new (mtClass) GrowableArray<int>(10, mtClass);
940 }
941 _subgraph_entry_fields->append(static_field_offset);
942 _subgraph_entry_fields->append(HeapShared::append_root(v));
943 }
944
945 // Add the Klass* for an object in the current KlassSubGraphInfo's subgraphs.
946 // Only objects of boot classes can be included in sub-graph.
947 void KlassSubGraphInfo::add_subgraph_object_klass(Klass* orig_k) {
948 assert(CDSConfig::is_dumping_heap(), "dump time only");
949 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(orig_k);
950
951 if (_subgraph_object_klasses == nullptr) {
952 _subgraph_object_klasses =
953 new (mtClass) GrowableArray<Klass*>(50, mtClass);
954 }
955
956 assert(ArchiveBuilder::current()->is_in_buffer_space(buffered_k), "must be a shared class");
957
958 if (_k == buffered_k) {
959 // Don't add the Klass containing the sub-graph to it's own klass
960 // initialization list.
961 return;
962 }
963
964 if (buffered_k->is_instance_klass()) {
965 if (!CDSConfig::is_dumping_invokedynamic()) {
966 // FIXME: this supports Lambda Proxy classes
967 assert(InstanceKlass::cast(buffered_k)->is_shared_boot_class(),
968 "must be boot class");
969 }
970 // vmClasses::xxx_klass() are not updated, need to check
971 // the original Klass*
972 if (orig_k == vmClasses::String_klass() ||
973 orig_k == vmClasses::Object_klass()) {
974 // Initialized early during VM initialization. No need to be added
975 // to the sub-graph object class list.
976 return;
977 }
978 check_allowed_klass(InstanceKlass::cast(orig_k));
979 } else if (buffered_k->is_objArray_klass()) {
980 Klass* abk = ObjArrayKlass::cast(buffered_k)->bottom_klass();
981 if (abk->is_instance_klass()) {
982 assert(InstanceKlass::cast(abk)->is_shared_boot_class(),
983 "must be boot class");
984 check_allowed_klass(InstanceKlass::cast(ObjArrayKlass::cast(orig_k)->bottom_klass()));
985 }
986 if (buffered_k == Universe::objectArrayKlass()) {
987 // Initialized early during Universe::genesis. No need to be added
988 // to the list.
989 return;
990 }
991 } else {
992 assert(buffered_k->is_typeArray_klass(), "must be");
993 // Primitive type arrays are created early during Universe::genesis.
994 return;
995 }
996
997 if (log_is_enabled(Debug, cds, heap)) {
998 if (!_subgraph_object_klasses->contains(buffered_k)) {
999 ResourceMark rm;
1000 log_debug(cds, heap)("Adding klass %s", orig_k->external_name());
1001 }
1002 }
1003
1004 _subgraph_object_klasses->append_if_missing(buffered_k);
1005 _has_non_early_klasses |= is_non_early_klass(orig_k);
1006 }
1007
1008 void KlassSubGraphInfo::check_allowed_klass(InstanceKlass* ik) {
1009 if (CDSConfig::is_dumping_invokedynamic()) {
1010 // FIXME -- this allows LambdaProxy classes
1011 return;
1012 }
1013 if (ik->module()->name() == vmSymbols::java_base()) {
1014 assert(ik->package() != nullptr, "classes in java.base cannot be in unnamed package");
1015 return;
1016 }
1017
1018 #ifndef PRODUCT
1019 if (!ik->module()->is_named() && ik->package() == nullptr) {
1020 // This class is loaded by ArchiveHeapTestClass
1021 return;
1022 }
1023 const char* extra_msg = ", or in an unnamed package of an unnamed module";
1024 #else
1025 const char* extra_msg = "";
1026 #endif
1027
1028 ResourceMark rm;
1029 log_error(cds, heap)("Class %s not allowed in archive heap. Must be in java.base%s",
1030 ik->external_name(), extra_msg);
1031 MetaspaceShared::unrecoverable_writing_error();
1032 }
1033
1034 bool KlassSubGraphInfo::is_non_early_klass(Klass* k) {
1035 if (k->is_objArray_klass()) {
1036 k = ObjArrayKlass::cast(k)->bottom_klass();
1037 }
1038 if (k->is_instance_klass()) {
1039 if (!SystemDictionaryShared::is_early_klass(InstanceKlass::cast(k))) {
1040 ResourceMark rm;
1041 log_info(cds, heap)("non-early: %s", k->external_name());
1042 return true;
1043 } else {
1044 return false;
1045 }
1046 } else {
1047 return false;
1048 }
1049 }
1050
1051 // Initialize an archived subgraph_info_record from the given KlassSubGraphInfo.
1052 void ArchivedKlassSubGraphInfoRecord::init(KlassSubGraphInfo* info) {
1053 _k = info->klass();
1054 _entry_field_records = nullptr;
1055 _subgraph_object_klasses = nullptr;
1056 _is_full_module_graph = info->is_full_module_graph();
1057
1058 if (_is_full_module_graph) {
1059 // Consider all classes referenced by the full module graph as early -- we will be
1060 // allocating objects of these classes during JVMTI early phase, so they cannot
1061 // be processed by (non-early) JVMTI ClassFileLoadHook
1062 _has_non_early_klasses = false;
1063 } else {
1064 _has_non_early_klasses = info->has_non_early_klasses();
1065 }
1066
1067 if (_has_non_early_klasses) {
1068 ResourceMark rm;
1069 log_info(cds, heap)(
1070 "Subgraph of klass %s has non-early klasses and cannot be used when JVMTI ClassFileLoadHook is enabled",
1071 _k->external_name());
1072 }
1073
1074 // populate the entry fields
1075 GrowableArray<int>* entry_fields = info->subgraph_entry_fields();
1076 if (entry_fields != nullptr) {
1077 int num_entry_fields = entry_fields->length();
1078 assert(num_entry_fields % 2 == 0, "sanity");
1079 _entry_field_records =
1080 ArchiveBuilder::new_ro_array<int>(num_entry_fields);
1081 for (int i = 0 ; i < num_entry_fields; i++) {
1082 _entry_field_records->at_put(i, entry_fields->at(i));
1083 }
1084 }
1085
1086 // the Klasses of the objects in the sub-graphs
1087 GrowableArray<Klass*>* subgraph_object_klasses = info->subgraph_object_klasses();
1088 if (subgraph_object_klasses != nullptr) {
1089 int num_subgraphs_klasses = subgraph_object_klasses->length();
1090 _subgraph_object_klasses =
1091 ArchiveBuilder::new_ro_array<Klass*>(num_subgraphs_klasses);
1092 for (int i = 0; i < num_subgraphs_klasses; i++) {
1093 Klass* subgraph_k = subgraph_object_klasses->at(i);
1094 if (log_is_enabled(Info, cds, heap)) {
1095 ResourceMark rm;
1096 log_info(cds, heap)(
1097 "Archived object klass %s (%2d) => %s",
1098 _k->external_name(), i, subgraph_k->external_name());
1099 }
1100 _subgraph_object_klasses->at_put(i, subgraph_k);
1101 ArchivePtrMarker::mark_pointer(_subgraph_object_klasses->adr_at(i));
1102 }
1103 }
1104
1105 ArchivePtrMarker::mark_pointer(&_k);
1106 ArchivePtrMarker::mark_pointer(&_entry_field_records);
1107 ArchivePtrMarker::mark_pointer(&_subgraph_object_klasses);
1108 }
1109
1110 class HeapShared::CopyKlassSubGraphInfoToArchive : StackObj {
1111 public:
1112 CompactHashtableWriter* _writer;
1113 CopyKlassSubGraphInfoToArchive(CompactHashtableWriter* writer) : _writer(writer) {}
1114
1115 bool do_entry(Klass* klass, KlassSubGraphInfo& info) {
1116 if (info.subgraph_object_klasses() != nullptr || info.subgraph_entry_fields() != nullptr) {
1117 ArchivedKlassSubGraphInfoRecord* record = HeapShared::archive_subgraph_info(&info);
1118 Klass* buffered_k = ArchiveBuilder::get_buffered_klass(klass);
1119 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary((address)buffered_k);
1120 u4 delta = ArchiveBuilder::current()->any_to_offset_u4(record);
1121 _writer->add(hash, delta);
1122 }
1123 return true; // keep on iterating
1124 }
1125 };
1126
1127 ArchivedKlassSubGraphInfoRecord* HeapShared::archive_subgraph_info(KlassSubGraphInfo* info) {
1128 ArchivedKlassSubGraphInfoRecord* record =
1129 (ArchivedKlassSubGraphInfoRecord*)ArchiveBuilder::ro_region_alloc(sizeof(ArchivedKlassSubGraphInfoRecord));
1130 record->init(info);
1131 return record;
1132 }
1133
1134 // Build the records of archived subgraph infos, which include:
1135 // - Entry points to all subgraphs from the containing class mirror. The entry
1136 // points are static fields in the mirror. For each entry point, the field
1137 // offset, and value are recorded in the sub-graph
1138 // info. The value is stored back to the corresponding field at runtime.
1139 // - A list of klasses that need to be loaded/initialized before archived
1140 // java object sub-graph can be accessed at runtime.
1141 void HeapShared::write_subgraph_info_table() {
1142 // Allocate the contents of the hashtable(s) inside the RO region of the CDS archive.
1143 DumpTimeKlassSubGraphInfoTable* d_table = _dump_time_subgraph_info_table;
1144 CompactHashtableStats stats;
1145
1146 _run_time_subgraph_info_table.reset();
1147
1148 CompactHashtableWriter writer(d_table->_count, &stats);
1149 CopyKlassSubGraphInfoToArchive copy(&writer);
1150 d_table->iterate(©);
1151 writer.dump(&_run_time_subgraph_info_table, "subgraphs");
1152
1153 _runtime_default_subgraph_info = archive_subgraph_info(_default_subgraph_info);
1154
1155 #ifndef PRODUCT
1156 if (ArchiveHeapTestClass != nullptr) {
1157 size_t len = strlen(ArchiveHeapTestClass) + 1;
1158 Array<char>* array = ArchiveBuilder::new_ro_array<char>((int)len);
1159 strncpy(array->adr_at(0), ArchiveHeapTestClass, len);
1160 _archived_ArchiveHeapTestClass = array;
1161 }
1162 #endif
1163 if (log_is_enabled(Info, cds, heap)) {
1164 print_stats();
1165 }
1166 }
1167
1168 void HeapShared::serialize_misc_info(SerializeClosure* soc) {
1169 soc->do_int(&_permobj_segments);
1170 }
1171
1172 void HeapShared::init_roots(oop roots_oop) {
1173 if (roots_oop != nullptr) {
1174 assert(ArchiveHeapLoader::is_in_use(), "must be");
1175 _roots = OopHandle(Universe::vm_global(), roots_oop);
1176 }
1177 }
1178
1179 void HeapShared::serialize_tables(SerializeClosure* soc) {
1180
1181 #ifndef PRODUCT
1182 soc->do_ptr(&_archived_ArchiveHeapTestClass);
1183 if (soc->reading() && _archived_ArchiveHeapTestClass != nullptr) {
1184 _test_class_name = _archived_ArchiveHeapTestClass->adr_at(0);
1185 setup_test_class(_test_class_name);
1186 }
1187 #endif
1188
1189 _run_time_subgraph_info_table.serialize_header(soc);
1190 soc->do_ptr(&_runtime_default_subgraph_info);
1191
1192 }
1193
1194 static void verify_the_heap(Klass* k, const char* which) {
1195 if (VerifyArchivedFields > 0) {
1196 ResourceMark rm;
1197 log_info(cds, heap)("Verify heap %s initializing static field(s) in %s",
1198 which, k->external_name());
1199
1200 VM_Verify verify_op;
1201 VMThread::execute(&verify_op);
1202
1203 if (VerifyArchivedFields > 1 && is_init_completed()) {
1204 // At this time, the oop->klass() of some archived objects in the heap may not
1205 // have been loaded into the system dictionary yet. Nevertheless, oop->klass() should
1206 // have enough information (object size, oop maps, etc) so that a GC can be safely
1207 // performed.
1208 //
1209 // -XX:VerifyArchivedFields=2 force a GC to happen in such an early stage
1210 // to check for GC safety.
1211 log_info(cds, heap)("Trigger GC %s initializing static field(s) in %s",
1212 which, k->external_name());
1213 FlagSetting fs1(VerifyBeforeGC, true);
1214 FlagSetting fs2(VerifyDuringGC, true);
1215 FlagSetting fs3(VerifyAfterGC, true);
1216 Universe::heap()->collect(GCCause::_java_lang_system_gc);
1217 }
1218 }
1219 }
1220
1221 // Before GC can execute, we must ensure that all oops reachable from HeapShared::roots()
1222 // have a valid klass. I.e., oopDesc::klass() must have already been resolved.
1223 //
1224 // Note: if a ArchivedKlassSubGraphInfoRecord contains non-early classes, and JVMTI
1225 // ClassFileLoadHook is enabled, it's possible for this class to be dynamically replaced. In
1226 // this case, we will not load the ArchivedKlassSubGraphInfoRecord and will clear its roots.
1227 void HeapShared::resolve_classes(JavaThread* current) {
1228 assert(CDSConfig::is_using_archive(), "runtime only!");
1229 if (!ArchiveHeapLoader::is_in_use()) {
1230 return; // nothing to do
1231 }
1232
1233 if (!CDSConfig::has_preloaded_classes()) {
1234 assert( _runtime_default_subgraph_info != nullptr, "must be");
1235 Array<Klass*>* klasses = _runtime_default_subgraph_info->subgraph_object_klasses();
1236 if (klasses != nullptr) {
1237 for (int i = 0; i < klasses->length(); i++) {
1238 Klass* k = klasses->at(i);
1239 ExceptionMark em(current); // no exception can happen here
1240 resolve_or_init(k, /*do_init*/false, current);
1241 }
1242 }
1243 }
1244
1245 resolve_classes_for_subgraphs(current, archive_subgraph_entry_fields);
1246 resolve_classes_for_subgraphs(current, fmg_archive_subgraph_entry_fields);
1247 }
1248
1249 void HeapShared::resolve_classes_for_subgraphs(JavaThread* current, ArchivableStaticFieldInfo fields[]) {
1250 for (int i = 0; fields[i].valid(); i++) {
1251 ArchivableStaticFieldInfo* info = &fields[i];
1252 TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name);
1253 InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name);
1254 assert(k != nullptr && k->is_shared_boot_class(), "sanity");
1255 resolve_classes_for_subgraph_of(current, k);
1256 }
1257 }
1258
1259 void HeapShared::resolve_classes_for_subgraph_of(JavaThread* current, Klass* k) {
1260 JavaThread* THREAD = current;
1261 ExceptionMark em(THREAD);
1262 const ArchivedKlassSubGraphInfoRecord* record =
1263 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/false, THREAD);
1264 if (HAS_PENDING_EXCEPTION) {
1265 CLEAR_PENDING_EXCEPTION;
1266 }
1267 if (record == nullptr) {
1268 clear_archived_roots_of(k);
1269 }
1270 }
1271
1272 void HeapShared::initialize_java_lang_invoke(TRAPS) {
1273 if (CDSConfig::is_loading_invokedynamic() || CDSConfig::is_dumping_invokedynamic()) {
1274 resolve_or_init("java/lang/invoke/Invokers$Holder", true, CHECK);
1275 resolve_or_init("java/lang/invoke/MethodHandle", true, CHECK);
1276 resolve_or_init("java/lang/invoke/MethodHandleNatives", true, CHECK);
1277 resolve_or_init("java/lang/invoke/DirectMethodHandle$Holder", true, CHECK);
1278 resolve_or_init("java/lang/invoke/DelegatingMethodHandle$Holder", true, CHECK);
1279 resolve_or_init("java/lang/invoke/LambdaForm$Holder", true, CHECK);
1280 resolve_or_init("java/lang/invoke/BoundMethodHandle$Species_L", true, CHECK);
1281 }
1282 }
1283
1284 void HeapShared::initialize_default_subgraph_classes(Handle loader, TRAPS) {
1285 if (!ArchiveHeapLoader::is_in_use()) {
1286 return;
1287 }
1288
1289 assert( _runtime_default_subgraph_info != nullptr, "must be");
1290 Array<Klass*>* klasses = _runtime_default_subgraph_info->subgraph_object_klasses();
1291 if (klasses != nullptr) {
1292 for (int pass = 0; pass < 2; pass ++) {
1293 for (int i = 0; i < klasses->length(); i++) {
1294 Klass* k = klasses->at(i);
1295 if (k->class_loader_data() == nullptr) {
1296 // This class is not yet loaded. We will initialize it in a later phase.
1297 continue;
1298 }
1299 if (k->class_loader() == loader()) {
1300 if (pass == 0) {
1301 if (k->is_instance_klass()) {
1302 InstanceKlass::cast(k)->link_class(CHECK);
1303 }
1304 } else {
1305 resolve_or_init(k, /*do_init*/true, CHECK);
1306 }
1307 }
1308 }
1309 }
1310 }
1311 }
1312
1313 void HeapShared::initialize_from_archived_subgraph(JavaThread* current, Klass* k) {
1314 JavaThread* THREAD = current;
1315 if (!ArchiveHeapLoader::is_in_use()) {
1316 return; // nothing to do
1317 }
1318
1319 ExceptionMark em(THREAD);
1320 const ArchivedKlassSubGraphInfoRecord* record =
1321 resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/true, THREAD);
1322
1323 if (HAS_PENDING_EXCEPTION) {
1324 CLEAR_PENDING_EXCEPTION;
1325 // None of the field value will be set if there was an exception when initializing the classes.
1326 // The java code will not see any of the archived objects in the
1327 // subgraphs referenced from k in this case.
1328 return;
1329 }
1330
1331 if (record != nullptr) {
1332 init_archived_fields_for(k, record);
1333 }
1334 }
1335
1336 const ArchivedKlassSubGraphInfoRecord*
1337 HeapShared::resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS) {
1338 assert(!CDSConfig::is_dumping_heap(), "Should not be called when dumping heap");
1339
1340 if (!k->is_shared()) {
1341 return nullptr;
1342 }
1343 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k);
1344 const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0);
1345
1346 #ifndef PRODUCT
1347 if (_test_class_name != nullptr && k->name()->equals(_test_class_name) && record != nullptr) {
1348 _test_class = k;
1349 _test_class_record = record;
1350 }
1351 #endif
1352
1353 // Initialize from archived data. Currently this is done only
1354 // during VM initialization time. No lock is needed.
1355 if (record == nullptr) {
1356 if (log_is_enabled(Info, cds, heap)) {
1357 ResourceMark rm(THREAD);
1358 log_info(cds, heap)("subgraph %s is not recorded",
1359 k->external_name());
1360 }
1361 return nullptr;
1362 } else {
1363 if (record->is_full_module_graph() && !CDSConfig::is_using_full_module_graph()) {
1364 if (log_is_enabled(Info, cds, heap)) {
1365 ResourceMark rm(THREAD);
1366 log_info(cds, heap)("subgraph %s cannot be used because full module graph is disabled",
1367 k->external_name());
1368 }
1369 return nullptr;
1370 }
1371
1372 if (record->has_non_early_klasses() && JvmtiExport::should_post_class_file_load_hook()) {
1373 if (log_is_enabled(Info, cds, heap)) {
1374 ResourceMark rm(THREAD);
1375 log_info(cds, heap)("subgraph %s cannot be used because JVMTI ClassFileLoadHook is enabled",
1376 k->external_name());
1377 }
1378 return nullptr;
1379 }
1380
1381 if (log_is_enabled(Info, cds, heap)) {
1382 ResourceMark rm;
1383 log_info(cds, heap)("%s subgraph %s ", do_init ? "init" : "resolve", k->external_name());
1384 }
1385
1386 if (do_init && k->name() == vmSymbols::java_lang_invoke_MethodType()) {
1387 // FIXME - hack.
1388 //
1389 // (The real fix would be to archive the MethodType class in its already initialized state. That
1390 // way we don't need to re-execute the <clinit> methods)
1391 //
1392 // We need to do this to break a cycle in the way the archived subgraphs are restored. Without this block, we
1393 // have the following sequence
1394 //
1395 // MethodType.<clinit>()
1396 // -> CDS.initializeFromArchive(MethodType.class);
1397 // -> (this "if" block)
1398 // -> resolve_or_init("MethodType", ...); // this does nothing because MethodType.<clinit> is already executing
1399 // -> resolve_or_init("DirectMethodHandle", ...); // this class is in record->subgraph_object_klasses();
1400 // -> DirectMethodHandle.<clinit>()
1401 // -> MethodType.methodType()
1402 // -> MethodType.genericMethodType()
1403 // -> aaload MethodType.objectOnlyTypes[n]; <<<< here
1404 //
1405 // We need to restore MethodType.objectOnlyTypes here, or else the above aaload will
1406 // get an NPE.
1407 Array<int>* entry_field_records = record->entry_field_records();
1408 assert(entry_field_records != nullptr, "must be");
1409 int efr_len = entry_field_records->length();
1410 assert(efr_len == 2, "must be");
1411 int root_index = entry_field_records->at(1);
1412 oop obj = get_root(root_index, /*clear=*/false);
1413 if (obj != nullptr) {
1414 objArrayOop archivedObjects = objArrayOop(obj);
1415 InstanceKlass* ik = InstanceKlass::cast(k);
1416 oop m = ik->java_mirror();
1417
1418 {
1419 fieldDescriptor fd;
1420 TempNewSymbol name = SymbolTable::new_symbol("archivedMethodTypes");
1421 TempNewSymbol sig = SymbolTable::new_symbol("Ljava/util/HashMap;");
1422 Klass* result = ik->find_field(name, sig, true, &fd);
1423 assert(result != nullptr, "must be");
1424 m->obj_field_put(fd.offset(), archivedObjects->obj_at(0));
1425 }
1426
1427 {
1428 fieldDescriptor fd;
1429 TempNewSymbol name = SymbolTable::new_symbol("objectOnlyTypes");
1430 TempNewSymbol sig = SymbolTable::new_symbol("[Ljava/lang/invoke/MethodType;");
1431 Klass* result = ik->find_field(name, sig, true, &fd);
1432 assert(result != nullptr, "must be");
1433 m->obj_field_put(fd.offset(), archivedObjects->obj_at(1));
1434 }
1435 }
1436 }
1437
1438 resolve_or_init(k, do_init, CHECK_NULL);
1439
1440 // Load/link/initialize the klasses of the objects in the subgraph.
1441 // nullptr class loader is used.
1442 Array<Klass*>* klasses = record->subgraph_object_klasses();
1443 if (klasses != nullptr) {
1444 for (int i = 0; i < klasses->length(); i++) {
1445 Klass* klass = klasses->at(i);
1446 if (!klass->is_shared()) {
1447 return nullptr;
1448 }
1449 resolve_or_init(klass, do_init, CHECK_NULL);
1450 }
1451 }
1452 }
1453
1454 return record;
1455 }
1456
1457 void HeapShared::resolve_or_init(const char* klass_name, bool do_init, TRAPS) {
1458 TempNewSymbol klass_name_sym = SymbolTable::new_symbol(klass_name);
1459 InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name_sym);
1460 if (k == nullptr) {
1461 return;
1462 }
1463 assert(k->is_shared_boot_class(), "sanity");
1464 resolve_or_init(k, false, CHECK);
1465 if (do_init) {
1466 resolve_or_init(k, true, CHECK);
1467 }
1468 }
1469
1470 void HeapShared::resolve_or_init(Klass* k, bool do_init, TRAPS) {
1471 if (!do_init) {
1472 if (k->class_loader_data() == nullptr) {
1473 Klass* resolved_k = SystemDictionary::resolve_or_null(k->name(), CHECK);
1474 assert(resolved_k == k, "classes used by archived heap must not be replaced by JVMTI ClassFileLoadHook");
1475 }
1476 } else {
1477 assert(k->class_loader_data() != nullptr, "must have been resolved by HeapShared::resolve_classes");
1478 if (k->is_instance_klass()) {
1479 InstanceKlass* ik = InstanceKlass::cast(k);
1480 ik->initialize(CHECK);
1481 } else if (k->is_objArray_klass()) {
1482 ObjArrayKlass* oak = ObjArrayKlass::cast(k);
1483 oak->initialize(CHECK);
1484 }
1485 }
1486 }
1487
1488 void HeapShared::init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record) {
1489 verify_the_heap(k, "before");
1490
1491 // Load the subgraph entry fields from the record and store them back to
1492 // the corresponding fields within the mirror.
1493 oop m = k->java_mirror();
1494 Array<int>* entry_field_records = record->entry_field_records();
1495 if (entry_field_records != nullptr) {
1496 int efr_len = entry_field_records->length();
1497 assert(efr_len % 2 == 0, "sanity");
1498 for (int i = 0; i < efr_len; i += 2) {
1499 int field_offset = entry_field_records->at(i);
1500 int root_index = entry_field_records->at(i+1);
1501 oop v = get_root(root_index, /*clear=*/true);
1502 m->obj_field_put(field_offset, v);
1503 log_debug(cds, heap)(" " PTR_FORMAT " init field @ %2d = " PTR_FORMAT, p2i(k), field_offset, p2i(v));
1504 }
1505
1506 // Done. Java code can see the archived sub-graphs referenced from k's
1507 // mirror after this point.
1508 if (log_is_enabled(Info, cds, heap)) {
1509 ResourceMark rm;
1510 log_info(cds, heap)("initialize_from_archived_subgraph %s " PTR_FORMAT "%s",
1511 k->external_name(), p2i(k), JvmtiExport::is_early_phase() ? " (early)" : "");
1512 }
1513 }
1514
1515 verify_the_heap(k, "after ");
1516 }
1517
1518 void HeapShared::clear_archived_roots_of(Klass* k) {
1519 unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k);
1520 const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0);
1521 if (record != nullptr) {
1522 Array<int>* entry_field_records = record->entry_field_records();
1523 if (entry_field_records != nullptr) {
1524 int efr_len = entry_field_records->length();
1525 assert(efr_len % 2 == 0, "sanity");
1526 for (int i = 0; i < efr_len; i += 2) {
1527 int root_index = entry_field_records->at(i+1);
1528 clear_root(root_index);
1529 }
1530 }
1531 }
1532 }
1533
1534 class WalkOopAndArchiveClosure: public BasicOopIterateClosure {
1535 int _level;
1536 bool _record_klasses_only;
1537 KlassSubGraphInfo* _subgraph_info;
1538 oop _referencing_obj;
1539 // The following are for maintaining a stack for determining
1540 // CachedOopInfo::_referrer
1541 static WalkOopAndArchiveClosure* _current;
1542 WalkOopAndArchiveClosure* _last;
1543 public:
1544 WalkOopAndArchiveClosure(int level,
1545 bool record_klasses_only,
1546 KlassSubGraphInfo* subgraph_info,
1547 oop orig) :
1548 _level(level),
1549 _record_klasses_only(record_klasses_only),
1550 _subgraph_info(subgraph_info),
1551 _referencing_obj(orig) {
1552 _last = _current;
1553 _current = this;
1554 }
1555 ~WalkOopAndArchiveClosure() {
1556 _current = _last;
1557 }
1558 void do_oop(narrowOop *p) { WalkOopAndArchiveClosure::do_oop_work(p); }
1559 void do_oop( oop *p) { WalkOopAndArchiveClosure::do_oop_work(p); }
1560
1561 protected:
1562 template <class T> void do_oop_work(T *p) {
1563 oop obj = RawAccess<>::oop_load(p);
1564 if (!CompressedOops::is_null(obj)) {
1565 size_t field_delta = pointer_delta(p, _referencing_obj, sizeof(char));
1566 if (!_record_klasses_only && log_is_enabled(Debug, cds, heap)) {
1567 ResourceMark rm;
1568 log_debug(cds, heap)("(%d) %s[" SIZE_FORMAT "] ==> " PTR_FORMAT " size " SIZE_FORMAT " %s", _level,
1569 _referencing_obj->klass()->external_name(), field_delta,
1570 p2i(obj), obj->size() * HeapWordSize, obj->klass()->external_name());
1571 if (log_is_enabled(Trace, cds, heap)) {
1572 LogTarget(Trace, cds, heap) log;
1573 LogStream out(log);
1574 obj->print_on(&out);
1575 }
1576 }
1577
1578 bool success = HeapShared::archive_reachable_objects_from(
1579 _level + 1, _subgraph_info, obj);
1580 assert(success, "VM should have exited with unarchivable objects for _level > 1");
1581 }
1582 }
1583
1584 public:
1585 static WalkOopAndArchiveClosure* current() { return _current; }
1586 oop referencing_obj() { return _referencing_obj; }
1587 KlassSubGraphInfo* subgraph_info() { return _subgraph_info; }
1588 };
1589
1590 WalkOopAndArchiveClosure* WalkOopAndArchiveClosure::_current = nullptr;
1591
1592 // Checks if an oop has any non-null oop fields
1593 class PointsToOopsChecker : public BasicOopIterateClosure {
1594 bool _result;
1595
1596 template <class T> void check(T *p) {
1597 _result |= (HeapAccess<>::oop_load(p) != nullptr);
1598 }
1599
1600 public:
1601 PointsToOopsChecker() : _result(false) {}
1602 void do_oop(narrowOop *p) { check(p); }
1603 void do_oop( oop *p) { check(p); }
1604 bool result() { return _result; }
1605 };
1606
1607 HeapShared::CachedOopInfo HeapShared::make_cached_oop_info(oop obj) {
1608 WalkOopAndArchiveClosure* walker = WalkOopAndArchiveClosure::current();
1609 oop referrer = (walker == nullptr) ? nullptr : walker->referencing_obj();
1610 PointsToOopsChecker points_to_oops_checker;
1611 obj->oop_iterate(&points_to_oops_checker);
1612 return CachedOopInfo(referrer, points_to_oops_checker.result());
1613 }
1614
1615 // We currently allow only the box classes, which are initialized very early by
1616 // HeapShared::init_box_classes().
1617 bool HeapShared::can_mirror_be_used_in_subgraph(oop orig_java_mirror) {
1618 return java_lang_Class::is_primitive(orig_java_mirror)
1619 || orig_java_mirror == vmClasses::Boolean_klass()->java_mirror()
1620 || orig_java_mirror == vmClasses::Character_klass()->java_mirror()
1621 || orig_java_mirror == vmClasses::Float_klass()->java_mirror()
1622 || orig_java_mirror == vmClasses::Double_klass()->java_mirror()
1623 || orig_java_mirror == vmClasses::Byte_klass()->java_mirror()
1624 || orig_java_mirror == vmClasses::Short_klass()->java_mirror()
1625 || orig_java_mirror == vmClasses::Integer_klass()->java_mirror()
1626 || orig_java_mirror == vmClasses::Long_klass()->java_mirror()
1627 || orig_java_mirror == vmClasses::Void_klass()->java_mirror()
1628 || orig_java_mirror == vmClasses::Object_klass()->java_mirror();
1629 }
1630
1631 void HeapShared::init_box_classes(TRAPS) {
1632 if (ArchiveHeapLoader::is_in_use()) {
1633 vmClasses::Boolean_klass()->initialize(CHECK);
1634 vmClasses::Character_klass()->initialize(CHECK);
1635 vmClasses::Float_klass()->initialize(CHECK);
1636 vmClasses::Double_klass()->initialize(CHECK);
1637 vmClasses::Byte_klass()->initialize(CHECK);
1638 vmClasses::Short_klass()->initialize(CHECK);
1639 vmClasses::Integer_klass()->initialize(CHECK);
1640 vmClasses::Long_klass()->initialize(CHECK);
1641 vmClasses::Void_klass()->initialize(CHECK);
1642 }
1643 }
1644
1645 void HeapShared::exit_on_error() {
1646 if (_context != nullptr) {
1647 ResourceMark rm;
1648 LogStream ls(Log(cds, heap)::error());
1649 ls.print_cr("Context");
1650 for (int i = 0; i < _context->length(); i++) {
1651 const char* s = _context->at(i);
1652 ls.print_cr("- %s", s);
1653 }
1654 }
1655 if (_trace != nullptr) {
1656 ResourceMark rm;
1657 LogStream ls(Log(cds, heap)::error());
1658 ls.print_cr("Reference trace");
1659 for (int i = 0; i < _trace->length(); i++) {
1660 oop orig_obj = _trace->at(i);
1661 ls.print_cr("[%d] ========================================", i);
1662 orig_obj->print_on(&ls);
1663 ls.cr();
1664 }
1665 }
1666 MetaspaceShared::unrecoverable_writing_error();
1667 }
1668
1669 // (1) If orig_obj has not been archived yet, archive it.
1670 // (2) If orig_obj has not been seen yet (since start_recording_subgraph() was called),
1671 // trace all objects that are reachable from it, and make sure these objects are archived.
1672 // (3) Record the klasses of all orig_obj and all reachable objects.
1673 bool HeapShared::archive_reachable_objects_from(int level,
1674 KlassSubGraphInfo* subgraph_info,
1675 oop orig_obj) {
1676 ArchivingObjectMark mark(orig_obj);
1677 assert(orig_obj != nullptr, "must be");
1678
1679 if (!JavaClasses::is_supported_for_archiving(orig_obj)) {
1680 // This object has injected fields that cannot be supported easily, so we disallow them for now.
1681 // If you get an error here, you probably made a change in the JDK library that has added
1682 // these objects that are referenced (directly or indirectly) by static fields.
1683 ResourceMark rm;
1684 log_error(cds, heap)("Cannot archive object of class %s", orig_obj->klass()->external_name());
1685 exit_on_error();
1686 }
1687
1688 #if 0
1689 if (java_lang_Class::is_instance(orig_obj) && subgraph_info != _default_subgraph_info) {
1690 if (can_mirror_be_used_in_subgraph(orig_obj)) {
1691 orig_obj = scratch_java_mirror(orig_obj);
1692 assert(orig_obj != nullptr, "must be archived");
1693 } else {
1694 // Don't follow the fields -- they will be nulled out when the mirror was copied
1695
1696 // FIXME - we should preserve the static fields of LambdaForm classes (and other hidden classes?)
1697 // so we need to walk the oop fields.
1698 orig_obj = scratch_java_mirror(orig_obj);
1699 assert(orig_obj != nullptr, "must be archived");
1700 }
1701 }
1702 #else
1703 if (java_lang_Class::is_instance(orig_obj)) {
1704 orig_obj = scratch_java_mirror(orig_obj);
1705 assert(orig_obj != nullptr, "must be archived");
1706 }
1707 #endif
1708
1709 if (has_been_seen_during_subgraph_recording(orig_obj)) {
1710 // orig_obj has already been archived and traced. Nothing more to do.
1711 return true;
1712 } else {
1713 set_has_been_seen_during_subgraph_recording(orig_obj);
1714 }
1715
1716 bool already_archived = has_been_archived(orig_obj);
1717 bool record_klasses_only = already_archived;
1718 if (!already_archived) {
1719 ++_num_new_archived_objs;
1720 if (!archive_object(orig_obj)) {
1721 // Skip archiving the sub-graph referenced from the current entry field.
1722 ResourceMark rm;
1723 log_error(cds, heap)(
1724 "Cannot archive the sub-graph referenced from %s object ("
1725 PTR_FORMAT ") size " SIZE_FORMAT ", skipped.",
1726 orig_obj->klass()->external_name(), p2i(orig_obj), orig_obj->size() * HeapWordSize);
1727 if (level == 1) {
1728 // Don't archive a subgraph root that's too big. For archives static fields, that's OK
1729 // as the Java code will take care of initializing this field dynamically.
1730 return false;
1731 } else {
1732 // We don't know how to handle an object that has been archived, but some of its reachable
1733 // objects cannot be archived. Bail out for now. We might need to fix this in the future if
1734 // we have a real use case.
1735 exit_on_error();
1736 }
1737 }
1738 }
1739
1740 Klass *orig_k = orig_obj->klass();
1741 subgraph_info->add_subgraph_object_klass(orig_k);
1742
1743 WalkOopAndArchiveClosure walker(level, record_klasses_only, subgraph_info, orig_obj);
1744 orig_obj->oop_iterate(&walker);
1745
1746 if (CDSEnumKlass::is_enum_obj(orig_obj)) {
1747 CDSEnumKlass::archive_enum_obj(level + 1, subgraph_info, orig_obj);
1748 }
1749 return true;
1750 }
1751
1752 //
1753 // Start from the given static field in a java mirror and archive the
1754 // complete sub-graph of java heap objects that are reached directly
1755 // or indirectly from the starting object by following references.
1756 // Sub-graph archiving restrictions (current):
1757 //
1758 // - All classes of objects in the archived sub-graph (including the
1759 // entry class) must be boot class only.
1760 // - No java.lang.Class instance (java mirror) can be included inside
1761 // an archived sub-graph. Mirror can only be the sub-graph entry object.
1762 //
1763 // The Java heap object sub-graph archiving process (see
1764 // WalkOopAndArchiveClosure):
1765 //
1766 // 1) Java object sub-graph archiving starts from a given static field
1767 // within a Class instance (java mirror). If the static field is a
1768 // reference field and points to a non-null java object, proceed to
1769 // the next step.
1770 //
1771 // 2) Archives the referenced java object. If an archived copy of the
1772 // current object already exists, updates the pointer in the archived
1773 // copy of the referencing object to point to the current archived object.
1774 // Otherwise, proceed to the next step.
1775 //
1776 // 3) Follows all references within the current java object and recursively
1777 // archive the sub-graph of objects starting from each reference.
1778 //
1779 // 4) Updates the pointer in the archived copy of referencing object to
1780 // point to the current archived object.
1781 //
1782 // 5) The Klass of the current java object is added to the list of Klasses
1783 // for loading and initializing before any object in the archived graph can
1784 // be accessed at runtime.
1785 //
1786 void HeapShared::archive_reachable_objects_from_static_field(InstanceKlass *k,
1787 const char* klass_name,
1788 int field_offset,
1789 const char* field_name) {
1790 assert(CDSConfig::is_dumping_heap(), "dump time only");
1791 assert(k->is_shared_boot_class(), "must be boot class");
1792
1793 oop m = k->java_mirror();
1794
1795 KlassSubGraphInfo* subgraph_info = get_subgraph_info(k);
1796 oop f = m->obj_field(field_offset);
1797
1798 log_debug(cds, heap)("Start archiving from: %s::%s (" PTR_FORMAT ")", klass_name, field_name, p2i(f));
1799
1800 if (!CompressedOops::is_null(f)) {
1801 if (log_is_enabled(Trace, cds, heap)) {
1802 LogTarget(Trace, cds, heap) log;
1803 LogStream out(log);
1804 f->print_on(&out);
1805 }
1806
1807 bool success = archive_reachable_objects_from(1, subgraph_info, f);
1808 if (!success) {
1809 log_error(cds, heap)("Archiving failed %s::%s (some reachable objects cannot be archived)",
1810 klass_name, field_name);
1811 } else {
1812 // Note: the field value is not preserved in the archived mirror.
1813 // Record the field as a new subGraph entry point. The recorded
1814 // information is restored from the archive at runtime.
1815 subgraph_info->add_subgraph_entry_field(field_offset, f);
1816 log_info(cds, heap)("Archived field %s::%s => " PTR_FORMAT, klass_name, field_name, p2i(f));
1817 }
1818 } else {
1819 // The field contains null, we still need to record the entry point,
1820 // so it can be restored at runtime.
1821 subgraph_info->add_subgraph_entry_field(field_offset, nullptr);
1822 }
1823 }
1824
1825 #ifndef PRODUCT
1826 class VerifySharedOopClosure: public BasicOopIterateClosure {
1827 public:
1828 void do_oop(narrowOop *p) { VerifySharedOopClosure::do_oop_work(p); }
1829 void do_oop( oop *p) { VerifySharedOopClosure::do_oop_work(p); }
1830
1831 protected:
1832 template <class T> void do_oop_work(T *p) {
1833 oop obj = RawAccess<>::oop_load(p);
1834 if (!CompressedOops::is_null(obj)) {
1835 HeapShared::verify_reachable_objects_from(obj);
1836 }
1837 }
1838 };
1839
1840 void HeapShared::verify_subgraph_from_static_field(InstanceKlass* k, int field_offset) {
1841 assert(CDSConfig::is_dumping_heap(), "dump time only");
1842 assert(k->is_shared_boot_class(), "must be boot class");
1843
1844 oop m = k->java_mirror();
1845 oop f = m->obj_field(field_offset);
1846 if (!CompressedOops::is_null(f)) {
1847 verify_subgraph_from(f);
1848 }
1849 }
1850
1851 void HeapShared::verify_subgraph_from(oop orig_obj) {
1852 if (!has_been_archived(orig_obj)) {
1853 // It's OK for the root of a subgraph to be not archived. See comments in
1854 // archive_reachable_objects_from().
1855 return;
1856 }
1857
1858 // Verify that all objects reachable from orig_obj are archived.
1859 init_seen_objects_table();
1860 verify_reachable_objects_from(orig_obj);
1861 delete_seen_objects_table();
1862 }
1863
1864 void HeapShared::verify_reachable_objects_from(oop obj) {
1865 _num_total_verifications ++;
1866 if (java_lang_Class::is_instance(obj)) {
1867 obj = scratch_java_mirror(obj);
1868 assert(obj != nullptr, "must be");
1869 }
1870 if (!has_been_seen_during_subgraph_recording(obj)) {
1871 set_has_been_seen_during_subgraph_recording(obj);
1872 assert(has_been_archived(obj), "must be");
1873 VerifySharedOopClosure walker;
1874 obj->oop_iterate(&walker);
1875 }
1876 }
1877 #endif
1878
1879 // The "default subgraph" contains special objects (see heapShared.hpp) that
1880 // can be accessed before we load any Java classes (including java/lang/Class).
1881 // Make sure that these are only instances of the very few specific types
1882 // that we can handle.
1883 void HeapShared::check_default_subgraph_classes() {
1884 GrowableArray<Klass*>* klasses = _default_subgraph_info->subgraph_object_klasses();
1885 int num = klasses->length();
1886 int warned = 0;
1887 for (int i = 0; i < num; i++) {
1888 Klass* subgraph_k = klasses->at(i);
1889 if (log_is_enabled(Info, cds, heap)) {
1890 ResourceMark rm;
1891 log_info(cds, heap)(
1892 "Archived object klass (default subgraph %d) => %s",
1893 i, subgraph_k->external_name());
1894 }
1895
1896 if (subgraph_k->is_instance_klass()) {
1897 InstanceKlass* ik = InstanceKlass::cast(subgraph_k);
1898 Symbol* name = ArchiveBuilder::current()->get_source_addr(ik->name());
1899 if (name != vmSymbols::java_lang_Class() &&
1900 name != vmSymbols::java_lang_String() &&
1901 name != vmSymbols::java_lang_ArithmeticException() &&
1902 name != vmSymbols::java_lang_ArrayIndexOutOfBoundsException() &&
1903 name != vmSymbols::java_lang_ArrayStoreException() &&
1904 name != vmSymbols::java_lang_ClassCastException() &&
1905 name != vmSymbols::java_lang_InternalError() &&
1906 name != vmSymbols::java_lang_NullPointerException() &&
1907 !is_archivable_hidden_klass(ik)) {
1908 ResourceMark rm;
1909 const char* category = ArchiveUtils::class_category(ik);
1910 log_info(cds)("TODO: Archived unusual klass (default subgraph %2d) => %-5s %s",
1911 ++warned, category, ik->external_name());
1912 }
1913 }
1914 }
1915 }
1916
1917 HeapShared::SeenObjectsTable* HeapShared::_seen_objects_table = nullptr;
1918 int HeapShared::_num_new_walked_objs;
1919 int HeapShared::_num_new_archived_objs;
1920 int HeapShared::_num_old_recorded_klasses;
1921
1922 int HeapShared::_num_total_subgraph_recordings = 0;
1923 int HeapShared::_num_total_walked_objs = 0;
1924 int HeapShared::_num_total_archived_objs = 0;
1925 int HeapShared::_num_total_recorded_klasses = 0;
1926 int HeapShared::_num_total_verifications = 0;
1927
1928 bool HeapShared::has_been_seen_during_subgraph_recording(oop obj) {
1929 return _seen_objects_table->get(obj) != nullptr;
1930 }
1931
1932 void HeapShared::set_has_been_seen_during_subgraph_recording(oop obj) {
1933 assert(!has_been_seen_during_subgraph_recording(obj), "sanity");
1934 _seen_objects_table->put_when_absent(obj, true);
1935 _seen_objects_table->maybe_grow();
1936 ++ _num_new_walked_objs;
1937 }
1938
1939 void HeapShared::start_recording_subgraph(InstanceKlass *k, const char* class_name, bool is_full_module_graph) {
1940 log_info(cds, heap)("Start recording subgraph(s) for archived fields in %s", class_name);
1941 init_subgraph_info(k, is_full_module_graph);
1942 init_seen_objects_table();
1943 _num_new_walked_objs = 0;
1944 _num_new_archived_objs = 0;
1945 _num_old_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses();
1946 }
1947
1948 void HeapShared::done_recording_subgraph(InstanceKlass *k, const char* class_name) {
1949 int num_new_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses() -
1950 _num_old_recorded_klasses;
1951 log_info(cds, heap)("Done recording subgraph(s) for archived fields in %s: "
1952 "walked %d objs, archived %d new objs, recorded %d classes",
1953 class_name, _num_new_walked_objs, _num_new_archived_objs,
1954 num_new_recorded_klasses);
1955
1956 delete_seen_objects_table();
1957
1958 _num_total_subgraph_recordings ++;
1959 _num_total_walked_objs += _num_new_walked_objs;
1960 _num_total_archived_objs += _num_new_archived_objs;
1961 _num_total_recorded_klasses += num_new_recorded_klasses;
1962 }
1963
1964 class ArchivableStaticFieldFinder: public FieldClosure {
1965 InstanceKlass* _ik;
1966 Symbol* _field_name;
1967 bool _found;
1968 int _offset;
1969 public:
1970 ArchivableStaticFieldFinder(InstanceKlass* ik, Symbol* field_name) :
1971 _ik(ik), _field_name(field_name), _found(false), _offset(-1) {}
1972
1973 virtual void do_field(fieldDescriptor* fd) {
1974 if (fd->name() == _field_name) {
1975 assert(!_found, "fields can never be overloaded");
1976 if (is_reference_type(fd->field_type())) {
1977 _found = true;
1978 _offset = fd->offset();
1979 }
1980 }
1981 }
1982 bool found() { return _found; }
1983 int offset() { return _offset; }
1984 };
1985
1986 void HeapShared::init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[],
1987 TRAPS) {
1988 for (int i = 0; fields[i].valid(); i++) {
1989 ArchivableStaticFieldInfo* info = &fields[i];
1990 TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name);
1991 TempNewSymbol field_name = SymbolTable::new_symbol(info->field_name);
1992 ResourceMark rm; // for stringStream::as_string() etc.
1993
1994 #ifndef PRODUCT
1995 bool is_test_class = (ArchiveHeapTestClass != nullptr) && (strcmp(info->klass_name, ArchiveHeapTestClass) == 0);
1996 const char* test_class_name = ArchiveHeapTestClass;
1997 #else
1998 bool is_test_class = false;
1999 const char* test_class_name = "";
2000 #endif
2001
2002 if (is_test_class) {
2003 log_warning(cds)("Loading ArchiveHeapTestClass %s ...", test_class_name);
2004 }
2005
2006 Klass* k = SystemDictionary::resolve_or_fail(klass_name, true, THREAD);
2007 if (HAS_PENDING_EXCEPTION) {
2008 CLEAR_PENDING_EXCEPTION;
2009 stringStream st;
2010 st.print("Fail to initialize archive heap: %s cannot be loaded by the boot loader", info->klass_name);
2011 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
2012 }
2013
2014 if (!k->is_instance_klass()) {
2015 stringStream st;
2016 st.print("Fail to initialize archive heap: %s is not an instance class", info->klass_name);
2017 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
2018 }
2019
2020 InstanceKlass* ik = InstanceKlass::cast(k);
2021 assert(InstanceKlass::cast(ik)->is_shared_boot_class(),
2022 "Only support boot classes");
2023
2024 if (is_test_class) {
2025 if (ik->module()->is_named()) {
2026 // We don't want ArchiveHeapTestClass to be abused to easily load/initialize arbitrary
2027 // core-lib classes. You need to at least append to the bootclasspath.
2028 stringStream st;
2029 st.print("ArchiveHeapTestClass %s is not in unnamed module", test_class_name);
2030 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
2031 }
2032
2033 if (ik->package() != nullptr) {
2034 // This restriction makes HeapShared::is_a_test_class_in_unnamed_module() easy.
2035 stringStream st;
2036 st.print("ArchiveHeapTestClass %s is not in unnamed package", test_class_name);
2037 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
2038 }
2039 } else {
2040 if (ik->module()->name() != vmSymbols::java_base()) {
2041 // We don't want to deal with cases when a module is unavailable at runtime.
2042 // FUTURE -- load from archived heap only when module graph has not changed
2043 // between dump and runtime.
2044 stringStream st;
2045 st.print("%s is not in java.base module", info->klass_name);
2046 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
2047 }
2048 }
2049
2050 if (is_test_class) {
2051 log_warning(cds)("Initializing ArchiveHeapTestClass %s ...", test_class_name);
2052 }
2053 ik->initialize(CHECK);
2054
2055 ArchivableStaticFieldFinder finder(ik, field_name);
2056 ik->do_local_static_fields(&finder);
2057 if (!finder.found()) {
2058 stringStream st;
2059 st.print("Unable to find the static T_OBJECT field %s::%s", info->klass_name, info->field_name);
2060 THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string());
2061 }
2062
2063 info->klass = ik;
2064 info->offset = finder.offset();
2065 }
2066 }
2067
2068 void HeapShared::init_subgraph_entry_fields(TRAPS) {
2069 assert(HeapShared::can_write(), "must be");
2070 _dump_time_subgraph_info_table = new (mtClass)DumpTimeKlassSubGraphInfoTable();
2071 init_subgraph_entry_fields(archive_subgraph_entry_fields, CHECK);
2072 if (CDSConfig::is_dumping_full_module_graph()) {
2073 init_subgraph_entry_fields(fmg_archive_subgraph_entry_fields, CHECK);
2074 }
2075 }
2076
2077 #ifndef PRODUCT
2078 void HeapShared::setup_test_class(const char* test_class_name) {
2079 ArchivableStaticFieldInfo* p = archive_subgraph_entry_fields;
2080 int num_slots = sizeof(archive_subgraph_entry_fields) / sizeof(ArchivableStaticFieldInfo);
2081 assert(p[num_slots - 2].klass_name == nullptr, "must have empty slot that's patched below");
2082 assert(p[num_slots - 1].klass_name == nullptr, "must have empty slot that marks the end of the list");
2083
2084 if (test_class_name != nullptr) {
2085 p[num_slots - 2].klass_name = test_class_name;
2086 p[num_slots - 2].field_name = ARCHIVE_TEST_FIELD_NAME;
2087 }
2088 }
2089
2090 // See if ik is one of the test classes that are pulled in by -XX:ArchiveHeapTestClass
2091 // during runtime. This may be called before the module system is initialized so
2092 // we cannot rely on InstanceKlass::module(), etc.
2093 bool HeapShared::is_a_test_class_in_unnamed_module(Klass* ik) {
2094 if (_test_class != nullptr) {
2095 if (ik == _test_class) {
2096 return true;
2097 }
2098 Array<Klass*>* klasses = _test_class_record->subgraph_object_klasses();
2099 if (klasses == nullptr) {
2100 return false;
2101 }
2102
2103 for (int i = 0; i < klasses->length(); i++) {
2104 Klass* k = klasses->at(i);
2105 if (k == ik) {
2106 Symbol* name;
2107 if (k->is_instance_klass()) {
2108 name = InstanceKlass::cast(k)->name();
2109 } else if (k->is_objArray_klass()) {
2110 Klass* bk = ObjArrayKlass::cast(k)->bottom_klass();
2111 if (!bk->is_instance_klass()) {
2112 return false;
2113 }
2114 name = bk->name();
2115 } else {
2116 return false;
2117 }
2118
2119 // See KlassSubGraphInfo::check_allowed_klass() - only two types of
2120 // classes are allowed:
2121 // (A) java.base classes (which must not be in the unnamed module)
2122 // (B) test classes which must be in the unnamed package of the unnamed module.
2123 // So if we see a '/' character in the class name, it must be in (A);
2124 // otherwise it must be in (B).
2125 if (name->index_of_at(0, "/", 1) >= 0) {
2126 return false; // (A)
2127 }
2128
2129 return true; // (B)
2130 }
2131 }
2132 }
2133
2134 return false;
2135 }
2136 #endif
2137
2138 void HeapShared::init_for_dumping(TRAPS) {
2139 if (HeapShared::can_write()) {
2140 setup_test_class(ArchiveHeapTestClass);
2141 _dumped_interned_strings = new (mtClass)DumpedInternedStrings(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE);
2142 init_subgraph_entry_fields(CHECK);
2143 }
2144 }
2145
2146 void HeapShared::archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
2147 bool is_full_module_graph) {
2148 _num_total_subgraph_recordings = 0;
2149 _num_total_walked_objs = 0;
2150 _num_total_archived_objs = 0;
2151 _num_total_recorded_klasses = 0;
2152 _num_total_verifications = 0;
2153
2154 // For each class X that has one or more archived fields:
2155 // [1] Dump the subgraph of each archived field
2156 // [2] Create a list of all the class of the objects that can be reached
2157 // by any of these static fields.
2158 // At runtime, these classes are initialized before X's archived fields
2159 // are restored by HeapShared::initialize_from_archived_subgraph().
2160 int i;
2161 for (int i = 0; fields[i].valid(); ) {
2162 ArchivableStaticFieldInfo* info = &fields[i];
2163 const char* klass_name = info->klass_name;
2164 start_recording_subgraph(info->klass, klass_name, is_full_module_graph);
2165
2166 ContextMark cm(klass_name);
2167 // If you have specified consecutive fields of the same klass in
2168 // fields[], these will be archived in the same
2169 // {start_recording_subgraph ... done_recording_subgraph} pass to
2170 // save time.
2171 for (; fields[i].valid(); i++) {
2172 ArchivableStaticFieldInfo* f = &fields[i];
2173 if (f->klass_name != klass_name) {
2174 break;
2175 }
2176
2177 ContextMark cm(f->field_name);
2178 archive_reachable_objects_from_static_field(f->klass, f->klass_name,
2179 f->offset, f->field_name);
2180 }
2181 done_recording_subgraph(info->klass, klass_name);
2182 }
2183
2184 log_info(cds, heap)("Archived subgraph records = %d",
2185 _num_total_subgraph_recordings);
2186 log_info(cds, heap)(" Walked %d objects", _num_total_walked_objs);
2187 log_info(cds, heap)(" Archived %d objects", _num_total_archived_objs);
2188 log_info(cds, heap)(" Recorded %d klasses", _num_total_recorded_klasses);
2189
2190 #ifndef PRODUCT
2191 for (int i = 0; fields[i].valid(); i++) {
2192 ArchivableStaticFieldInfo* f = &fields[i];
2193 verify_subgraph_from_static_field(f->klass, f->offset);
2194 }
2195 log_info(cds, heap)(" Verified %d references", _num_total_verifications);
2196 #endif
2197 }
2198
2199 // Not all the strings in the global StringTable are dumped into the archive, because
2200 // some of those strings may be only referenced by classes that are excluded from
2201 // the archive. We need to explicitly mark the strings that are:
2202 // [1] used by classes that WILL be archived;
2203 // [2] included in the SharedArchiveConfigFile.
2204 void HeapShared::add_to_dumped_interned_strings(oop string) {
2205 assert_at_safepoint(); // DumpedInternedStrings uses raw oops
2206 assert(!ArchiveHeapWriter::is_string_too_large_to_archive(string), "must be");
2207 bool created;
2208 _dumped_interned_strings->put_if_absent(string, true, &created);
2209 if (created) {
2210 _dumped_interned_strings->maybe_grow();
2211 }
2212 }
2213
2214 #ifndef PRODUCT
2215 // At dump-time, find the location of all the non-null oop pointers in an archived heap
2216 // region. This way we can quickly relocate all the pointers without using
2217 // BasicOopIterateClosure at runtime.
2218 class FindEmbeddedNonNullPointers: public BasicOopIterateClosure {
2219 void* _start;
2220 BitMap *_oopmap;
2221 int _num_total_oops;
2222 int _num_null_oops;
2223 public:
2224 FindEmbeddedNonNullPointers(void* start, BitMap* oopmap)
2225 : _start(start), _oopmap(oopmap), _num_total_oops(0), _num_null_oops(0) {}
2226
2227 virtual void do_oop(narrowOop* p) {
2228 assert(UseCompressedOops, "sanity");
2229 _num_total_oops ++;
2230 narrowOop v = *p;
2231 if (!CompressedOops::is_null(v)) {
2232 size_t idx = p - (narrowOop*)_start;
2233 _oopmap->set_bit(idx);
2234 } else {
2235 _num_null_oops ++;
2236 }
2237 }
2238 virtual void do_oop(oop* p) {
2239 assert(!UseCompressedOops, "sanity");
2240 _num_total_oops ++;
2241 if ((*p) != nullptr) {
2242 size_t idx = p - (oop*)_start;
2243 _oopmap->set_bit(idx);
2244 } else {
2245 _num_null_oops ++;
2246 }
2247 }
2248 int num_total_oops() const { return _num_total_oops; }
2249 int num_null_oops() const { return _num_null_oops; }
2250 };
2251 #endif
2252
2253 #ifndef PRODUCT
2254 ResourceBitMap HeapShared::calculate_oopmap(MemRegion region) {
2255 size_t num_bits = region.byte_size() / (UseCompressedOops ? sizeof(narrowOop) : sizeof(oop));
2256 ResourceBitMap oopmap(num_bits);
2257
2258 HeapWord* p = region.start();
2259 HeapWord* end = region.end();
2260 FindEmbeddedNonNullPointers finder((void*)p, &oopmap);
2261
2262 int num_objs = 0;
2263 while (p < end) {
2264 oop o = cast_to_oop(p);
2265 o->oop_iterate(&finder);
2266 p += o->size();
2267 ++ num_objs;
2268 }
2269
2270 log_info(cds, heap)("calculate_oopmap: objects = %6d, oop fields = %7d (nulls = %7d)",
2271 num_objs, finder.num_total_oops(), finder.num_null_oops());
2272 return oopmap;
2273 }
2274
2275 #endif // !PRODUCT
2276
2277 void HeapShared::count_allocation(size_t size) {
2278 _total_obj_count ++;
2279 _total_obj_size += size;
2280 for (int i = 0; i < ALLOC_STAT_SLOTS; i++) {
2281 if (size <= (size_t(1) << i)) {
2282 _alloc_count[i] ++;
2283 _alloc_size[i] += size;
2284 return;
2285 }
2286 }
2287 }
2288
2289 static double avg_size(size_t size, size_t count) {
2290 double avg = 0;
2291 if (count > 0) {
2292 avg = double(size * HeapWordSize) / double(count);
2293 }
2294 return avg;
2295 }
2296
2297 void HeapShared::print_stats() {
2298 size_t huge_count = _total_obj_count;
2299 size_t huge_size = _total_obj_size;
2300
2301 for (int i = 0; i < ALLOC_STAT_SLOTS; i++) {
2302 size_t byte_size_limit = (size_t(1) << i) * HeapWordSize;
2303 size_t count = _alloc_count[i];
2304 size_t size = _alloc_size[i];
2305 log_info(cds, heap)(SIZE_FORMAT_W(8) " objects are <= " SIZE_FORMAT_W(-6)
2306 " bytes (total " SIZE_FORMAT_W(8) " bytes, avg %8.1f bytes)",
2307 count, byte_size_limit, size * HeapWordSize, avg_size(size, count));
2308 huge_count -= count;
2309 huge_size -= size;
2310 }
2311
2312 log_info(cds, heap)(SIZE_FORMAT_W(8) " huge objects (total " SIZE_FORMAT_W(8) " bytes"
2313 ", avg %8.1f bytes)",
2314 huge_count, huge_size * HeapWordSize,
2315 avg_size(huge_size, huge_count));
2316 log_info(cds, heap)(SIZE_FORMAT_W(8) " total objects (total " SIZE_FORMAT_W(8) " bytes"
2317 ", avg %8.1f bytes)",
2318 _total_obj_count, _total_obj_size * HeapWordSize,
2319 avg_size(_total_obj_size, _total_obj_count));
2320 }
2321
2322 bool HeapShared::is_archived_boot_layer_available(JavaThread* current) {
2323 TempNewSymbol klass_name = SymbolTable::new_symbol(ARCHIVED_BOOT_LAYER_CLASS);
2324 InstanceKlass* k = SystemDictionary::find_instance_klass(current, klass_name, Handle(), Handle());
2325 if (k == nullptr) {
2326 return false;
2327 } else {
2328 TempNewSymbol field_name = SymbolTable::new_symbol(ARCHIVED_BOOT_LAYER_FIELD);
2329 TempNewSymbol field_signature = SymbolTable::new_symbol("Ljdk/internal/module/ArchivedBootLayer;");
2330 fieldDescriptor fd;
2331 if (k->find_field(field_name, field_signature, true, &fd) != nullptr) {
2332 oop m = k->java_mirror();
2333 oop f = m->obj_field(fd.offset());
2334 if (CompressedOops::is_null(f)) {
2335 return false;
2336 }
2337 } else {
2338 return false;
2339 }
2340 }
2341 return true;
2342 }
2343
2344 #endif // INCLUDE_CDS_JAVA_HEAP